XML 64 R46.htm IDEA: XBRL DOCUMENT
v3.22.4

Note 5 - Bank Debt - Maximum Leverage Ratio (Details) - Credit Agreement [Member] | Dec. 31, 2022
--- | ---
Maximum Leverage Ratio | 2.25
Period Ending June 30, 2022 [Member] |
Maximum Leverage Ratio | 2.50

X
- Definition The maximum leverage ratio (consolidated funded debt / trailing twelve months adjusted EBITDA) under the covenant of the debt instrument. + References No definition available. + Details
Name: | hnrg_DebtInstrumentCovenantMaximumLeverageRatio
Namespace Prefix: | hnrg_
Data Type: | xbrli:pureItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | us-gaap_DebtInstrumentAxis=hnrg_CreditAgreementMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_StatementScenarioAxis=hnrg_PeriodEndingJune302022Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |